Gallows humour

If people try to make fun or laugh when things are very frightening, dangerous, life-threatening or hopeless, it is gallows humour (or "gallows humor").

Game on

When someone says 'Game on!', it means that they are accepting a challenge or ready to get something done.

Game plan

A game plan is a strategy.

Garbage fee

A garbage fee is a charge that has no value and doesn't provide any real service.

Garbage in, garbage out

If a computer system or database is built badly, then the results will be bad.

Gardening leave

(UK) If someone is paid for a period when they are not working, either after they have given in their notice or when they are being investigated, they are on gardening leave.

Gather pace

If events gather pace, they move faster.

Gather steam

If something gathers speed, it moves or progresses at an increasing speed.

Get a grip

If you get a grip, you control your emotions so that they don't overwhelm you.

Get a handle on

When you get a handle on something, you come to understand it.

Get a sheepskin

Getting a sheepskin (or your sheepskin) means getting a degree or diploma.  (Sheepskin refers to the parchment that a degree is printed on-  parchment comes from sheepskin.)

Get along famously

If people get along famously, they have an exceedingly good relationship.

Get away scot-free

If someone gets away scot-free, they are not punished when they have done something wrong. ('Get off scot-free' is an alternative.)

Get away with murder

If you get away with murder, you do something bad and don't get caught or punished.('Get away with blue murder' is also used.)

Get back on the horse that bucked you

When you start drinking again after being hungover from drinking the previous night.

Get cracking

To get cracking means to start working on something, usually a job or task with defined parameters.

Get in on the act

If people want to get in on the act, they want to participate in something that is currently profitable or popular.

Get in on the ground floor

If you get in on the ground floor, you enter a project or venture at the start before people know how successful it might be.

Get it in the neck

(UK) If you get it in the neck, you are punished or criticised for something.

Get it off your chest

If you get something off your chest, you confess to something that has been troubling you.

Get my drift

If you get someone's drift, you understand what they are trying to say. ('Catch their drift' is an alternative form.)

Get off the ground

If a project or plan gets off the ground, it starts to be put into operation.

Get on like a house on fire

If people get on like a house on fire, they have a very close and good relationship.

Get on my last nerve

(USA) If something is getting on your last nerve, you are completely fed up, ready to lose your temper. (Southern USA)

Get on your nerves

If something gets on your nerves, it annoys or irritates you.

Get on your soapbox

If someone on their soapbox, they hold forth (talk a lot) about a subject they feel strongly about.

Get out of bed on the wrong side

If you get out of bed on the wrong side, you wake up and start the day in a bad mood for no real reason.

Get out of your pram

(UK) If someone gets out of their pram, they respond aggressively to an argument or problem that doesn't involve them.

Get the axe

If you get the axe, you lose your job.  ('Get the ax' is the American spelling.)

Get the ball rolling

If you get the ball rolling, you start something so that it can start making progress.

Get the green light

If you get the green light to do something, you are given the necessary permission, authorisation.

Get the hang of it

When you get the hang of something, you are familiar with it and know how to do it.

Get the lead out

This is used to tell someone to hurry up.

Get the monkey off your back

If you get the monkey off your back, you pass on a problem to someone else.

Get the nod

(UK) If you get the nod to something, you get approval or permission to do it.

Get the picture

If you get the picture, you understand a situation fully.

Get the show on the road

If you get the show on the road, you put a plan into operation or begin something.

Get to grips

If you get to grips with something, you take control and do it properly.

Get up and go

If someone has lots of get up and go, they have lots of enthusiasm and energy.

Get wind of

If you get wind of something, you hear or learn about it, especially if it was meant to be secret.

Get your ducks in a row

If you get your ducks in a row, you organise yourself and your life.

Get your feathers in a bunch

If you get your feathers in a bunch, you get upset or angry about something.

Get your feet wet

If you get your feet wet, you gain your first experience of something.

Get your goat

If something gets your goat, it annoys you.

Get your hands dirty

If you get your hands dirty, you become involved in something where the realities might compromise your principles. It can also mean that a person is not just stuck in an ivory tower dictating strategy, but is prepared to put in the effort and hard work to make the details actually happen.

Get your head around something

If you get your head around something, you come to understand it even though it is difficult to comprehend.

Get your skates on

This is used as a way of telling people to hurry up.

Get your teeth into

If you get your teeth into something, you become involved in or do something that is intellectually challenging or satisfying.  ('Dig you teeth into' and 'sink your teeth into' are also used.)

Get your wires crossed

If people get their wires cross, they misunderstand each other, especially when making arrangements.  ('Get your lines crossed' is also used.)

Ghost of a chance

If something or someone hasn't got a ghost of a chance, they have no hope whatsoever of succeeding.

Ghostly presence

You can feel or otherwise sense a ghostly presence, but you cannot do it clearly only vaguely.

Gift of the gab

If someone has the gift of the gab, they speak in a persuasive and interesting way.

Gild the lily

If you gild the lily, you decorate something that is already ornate.